z22 and L20b crank ?s

[datsunfish]

I have been planning on building a 2.3 motor from a z22 I have. It needs an overbore so I figured I would go with the ka pistons. According to the Jason Grey info I need to use the z22 crank but it can be in either a z22 or L20b block. Would I be able to use a L20b crank instead for the counterweight factor. Is there a different stroke to the cranks? Would it be fine with the z22 crank or would I have a lower rev limitation that could lead to premature wear or breakage?

I figure after the first of the year I should have all the junk I need. I only need the pistons a L20b timing cover and maybe a L20b crank. I want to go full out wicked fast sleeper on the 521 rat and keep the others for more functional use.

[510er]

I am building a L20 block with Z22 crank rods and pistons. I have an extra L20 block L18 block 2 L20 cranks and 2 sets of L20 pistons, and 1 set of rods.

[datzenmike]

Z22 and L20B have different stroke.

 

If you want to use the fully counter weighted L20B crank with Z22 block and KA/Z24 pistons you will have a motor of 2.138 liters in size:

 

Over bore the 87mm Z22 block to the KA or Z24 piston size of 89mm.

You will need Z22E rods that are 149.5mm long producing a -0.95mm deck height.

 

All the above with 45.2cc open chamber head and 2.8cc dish KA24E pistons gives a compression of: 9.714

 

All the above with 45.2cc open chamber head and 15cc dish Z-24 pistons gives a compression of 8.269

 

All the above with closed 41cc P-nut head and 2.8cc KA24E pistons gives a compression of 10.355

 

All the above with closed 41cc P-nut head and 15cc Z-24 pistons gives a compression of 8.709

Edited December 5, 2008 by datzenmike

[hang_510]

where do you calculate that info from mike?

 

Z22 and L20B have different stroke.

92 mm VS. 86 mm

 

 

using the L20 crank in a Z22 w/Z22E rods/pistons(dished) and U67 head, your looking a good turbo candidate setup... ~7.5:1

 

 

i have a set of Z22e rods and a set of forged domed arias pistons @ 88mm avail.(w/ 35.5mm pin height=Z22S) would put you ~9.4:1

 

 

 

whadya have to go a put more crazy ideas in my head for :fu:

[datzenmike]

where do you calculate that info from mike?

 

 

 

A few Jason Gray specs and a hand held h/p 48G. 1/2 bore squared x pi x deck or bore open or closed head volume + piston dish and divide by something.

[fiveNdime]

I'm going to toss my 2 cents for what I know. I have a Z22 in my 521 with stock bottom guts and L head, and it runs awesome. I do know however that as long as you have a good block which are hard to find not cracked then you can bore it I think 160 over or something like that to fit the KA pistons. The Z22 must come out of the early 80's truck because it has the capability of still having the water jackets far enough away from the cylinder after you have put the KA pistons in.....done! Cracks are always going to be in the center head bolt hole on the block....in that area.

[datzenmike]

Block cracks are over rated. It's not a crank or connecting rod. As long as there are no coolant leaks. A minor hairline indicates a stressed area has relieved itself just like an earthquake. Once relieved the area is seasoned. If a shop looks hard enough they'll find cracks on any block. Big deal, most cracked blocks are out there being driven daily with no problems at all. A good gasket, clean surfaces and proper torque procedure will cover it and you'll never have a problem with it.

[fiveNdime]

Block cracks are over rated. It's not a crank or connecting rod. As long as there are no coolant leaks. A minor hairline indicates a stressed area has relieved itself just like an earthquake. Once relieved the area is seasoned. If a shop looks hard enough they'll find cracks on any block. Big deal, most cracked blocks are out there being driven daily with no problems at all. A good gasket, clean surfaces and proper torque procedure will cover it and you'll never have a problem with it.

 

 

Well you could do things half ass...which most people do but I would start with a "good" block. I also suppose that any machine shop would tell you its ok to use a cracked block??? They are cracked for a reason, too much stress at one point equals failure at another point simple as that. You can put a band-aid over it and simply use it but I don,t recommend if you want to do it right.

 

Mike: nothing against ya.

[datzenmike]

I hear ya. I would rather have a good block and if I was building a race motor or hot street motor I wouldn't think about using it. A machine shop would sure say no because they have no way of knowing how you are going to run it. They don't want to risk a customer coming back.

 

It's a matter of degree. If I tore a good runner down to 'freshen it up' and found a hair line crack I sure wouldn't chuck it. At least not outright. After all it was running just fine for every day use for years and the only thing different is that before, no-one knew it was there and now you do. I'd be less inclined to worry about a motor for my own use. Half assed or risk management?

[fiveNdime]

Fiar, but at least do me this one favor if building a motor or rebuilding a motor. CHASE all the treads with a tap, and Use new head bolts if you have the cash. The Z22 is especially prone to create cracks when you bottom out used bolts because they are stretched. Trust me on this.:D

[ppeters914]

I have been planning on building a 2.3 motor from a z22 I have. It needs an overbore so I figured I would go with the KA pistons.

 

Here ya go:

 

http://forum.ratsun.net/showthread.php?t=7121